Today, the United States sent a warning to North Korea by deploying two nuclear-capable B-2 bombers to drop munitions near North Korea in a joint military drill with South Korea. The Associated Press called the muscle-flexing "unprecedented." Time’s ace defense writer Mark Thompson deemed the military’s announcement "unusual."

One of the reasons the U.S. warning shot is atypical is because the United States rarely announces the location of its top-secret B-2 bombers. But another reason this is uncharted territory is because of the exorbitant expense of taking B-2 bombers out of their home base in Missouri to frighten a bellicose regime on the other side of the world. As the Center for Public Integrity reported last year:

The B-2s are actually not used much now, partly because few targets justify risking aircraft that cost $3 billion apiece in today’s dollars, and partly because their flights by some estimates cost $135,000 per hour – almost double that of any other military airplane.

$135,000 per hour of flight? That’s a steep price tag, especially considering the flight was round-trip and involved two stealth bombers. Per the military’s statement:

This mission by two B-2 Spirit bombers assigned to 509th Bomb Wing … involved flying more than 6,500 miles to the Korean Peninsula, dropping inert munitions on the Jik Do Range, and returning to the continental U.S. in a single, continuous mission.

The military didn’t say how many hours the B-2s were in the air. But even if the B-2s were traveling at top speed the entire way (628 mph), which they most certainly were not, it would mean 10.3 hours each way — a tally that doesn’t even include the amount of time it took to drop the munitions on the South Korean island. Adding it all up, that’s 20.6 hours of flight time for two B-2 bombers — for an estimated cost of $5.5 million.

That may be a rounding error given the scope of the Pentagon’s budget, but the costs don’t stop there. According to a Los Angeles Times report on the B-2 bombers in 2010, the after-flight maintenance costs of such an operation will really burn a hole in your pocket. "For each hour it’s in the air, a bomber spends 50 to 60 hours on the ground undergoing maintenance," reported the paper. "The Air Force spent more than $800 million last year upgrading, maintaining and overhauling the stealth bomber fleet."

Let’s just hope the Dear Leader was sufficiently spooked. This could get expensive.